Memory devices are typically provided as internal, semiconductor, integrated circuit devices in computers or other electronic devices. There are many different types of memory including random-access memory (RAM), read only memory (ROM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), and flash memory.
Flash memory devices have developed into a popular source of non-volatile memory for a wide range of electronic applications. Flash memory devices typically use a one-transistor memory cell that allows for high memory densities, high reliability, and low power consumption. Changes in threshold voltage of the memory cells, through programming (which is often referred to as writing) of data-storage structures, using charge-storage structures (e.g., floating gates or charge traps) or other physical phenomena (e.g., phase change or polarization), determine the data state of each cell. Common uses for flash memory include personal computers, personal digital assistants (PDAs), digital cameras, digital media players, cellular telephones, solid state drives and removable memory modules, and the uses are growing.
There is a continuing desire to increase memory density, e.g., the number of bits of data that can be stored for a given integrated circuit die area. However, as memory density increases, the device structures often become smaller, and fabrication of these structures becomes more critical. For example, device structures are often formed by depositing layers of materials of different compositions, and selectively removing portions of these layers, such as by isotropic or anisotropic removal techniques. As these structures become smaller, selectivity of the removal technique, i.e., the ability to remove one material while maintaining the integrity of adjacent, dissimilar materials, becomes more important.
For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for alternative methods for facilitating improvements in formation of structures for integrated circuit devices.